go/src/crypto/internal/cryptotest/block.go

type MakeBlock …

// TestBlock performs a set of tests on cipher.Block implementations, checking
// the documented requirements of BlockSize, Encrypt, and Decrypt.
func TestBlock(t *testing.T, keySize int, mb MakeBlock) { … }

func testCipher(t *testing.T, cipher func(dst, src []byte), blockSize int) { … }

func mustPanic(t *testing.T, msg string, f func()) { … }